Leaking 727

[a100terry]

Hi Guys
Had an oil leak on the bottom of the bell housing. The fluid level was correct ie. not overfilled, so ended up taking the box out and replacing the oil seal. Reassembled everything and took it for a road test - it was still leaking.

Am I right in thinking that there are only two places that oil can come from - the seal and the vent hole? Is it possible I have snagged the new oil seal on re-assembly? (I was taking care but it wasn't easy - the converter didn't want to click in)

All thoughts much appreciated

[a100terry]

Just to add to the info above. When ordering a new oil seal from a parts person, he advised that I should replace the oil pump bushing, which is just behind the oil seal (I think). If this was worn, would it really cause the oil seal to leak?

The gearbox was overhauled by Blue 30,000 miles ago (2006) and has been perfect up to now. It has a nice life - in a camper van and doesn’t do drag racing!

Many thanks - Terry

[Blue]

When you took the box out was it wet below the seal area inside the bell housing? There would be fluid on the face of the pump if the pump seal was leaking, if it's dry the fluid is finding it's way to the bell housing from elsewhere.

[a100terry]

Thanks Blue. From memory, the whole area was damp. I am about to take the box out again (‘m too old for this!) and will inspect it all a bit more carefully.

[a100terry]

Box came out for the second time. On inspection, the oil seal was ok but there was play in the metal bush in the oil pump. Apparently this can sometimes cause problems when worn. I replaced the bush and fitted a new oil seal together with the two outer gaskets of the pump housing. Then put the gear box back in.
Took it for a test drive and it still leaked

I am now very confused. Is overfilling the ATF the only reason for oil coming out of the vent hole? I don’t know whether that is where the oil is coming from, but it is a possibility. And I obviously haven’t overfilled it.

Any thoughts would be welcome.
Terry

[TW71]

Any news or results?

[aussie pete]

Another place that can cause a leak is the o ring at the bottom of the dipstick tube,....I have been there and done that